In a sauce pan, combine milk, sugar, coffee and cocoa.
Bring it to boil.
Remove from flame and allow it to cool completely.
Chill this overnight.
On the day of serving, whip the cream with 1/4 tsp of instant coffee until soft peaks form.
Whip the cold mocha until slightly frothy.
Pour it into the serving glass and top it with whipped coffee cream.
Serve it immediately.